Triangle.



W. G. GLASSON.

TRIANGLE.

APPLICATION FILED D110. 7, 1912.

1, 101, 1 1 9, Patented June 23, 1914.

COLUMBIA PLANOnRAm-l co., WASHINGTON, D. c.

WALTER G. CLASSON, OE LEOMINSTEB, MASSACHU$ETT$ TRIANGLE.

Specification of Letters Patent.

Patented June 2 3, 1914.

Application filed December '7, 1912. Serial No. 735,891.

To all whom it may concern:

Be it known that I. VVALTER G. CLASSON,

a citizen of the United States, residing at Leominster, county of\Vorcester, State of Massachusetts, have invented an Improvement inTriangles, of which the following description, in connection with theaccompanying drawing, is a specification, like characters on the drawingrepresenting like arts.

p This invention relates totriangles such as draftsmen use, and it hasfor its object to provide a novel triangle with a sliding scale whichfacilitates greatly the operation of plotting out streets, lots, houses,etc.

I will first describe one embodiment of my invention and then point outthe novel features in the appended claims.

Referring to the drawings, Figure 1 is a perspective view of a triangleembodying my invention; Fig. 2 is a section on the line :c:c, Fig. 1;Fig. 3 shows how the triangle may be used for plotting lots, houses onlots, etc.

1 designates a triangle such as draftsmen commonly use and which isprovided with the two edges 2 and 3 extending at right angles to eachother as usual in triangles. Slidably on the triangle and adjacent eachof the edges 2 and 3 is a sliding scale, said scales being designated 4:and 5, respectively. Each scale is mounted to move longitudinally of andparallel to the adjacent edge of the triangle, and the outer edge 6 ofthe scale comes flush with the edge of the triangle. These slidingscales 4 and 5 are preferably provided with bevel surfaces 7 which areproperly graduated, and they are mounted on the triangle so that theycan be reversed. There are various ways in which these scales may besecured to the triangle. As herein shown the triangle has rigidtherewith two dove-tailed tracks 8 and the sliding scales are each madewith dovetailed grooves 19 to fit the tracks." The tracks are soarranged that each scale can move clear to and beyond the right angleedge of the triangle which stands perpendicular to the scale, that is,.the scale a can be moved into the dotted line position to projectbeyond the edge 3 and the scale 5 can be moved so as to project beyondthe edge 2. I secure this end by making the ends 9 of the tracks 8situated a distance from the right an "is edges of the triangle equal atleast to t e Width of the scale, so

that each scale can move by the end of the track on which the otherscale is mounted. These sliding scales will preferably he graduated ontheir edges to represent a scale of an inch to the foot or a quarter ofan inch to the foot, or any other similar reduction.

A triangle having this invention is especially useful in plottingstreets, lots, houses on lots, etc, as shown in Fig. 3. Assuming that 10is a sheet of paper on which street, lots and houses are to be laid out,and that 11 represents the street and it is desired to lay off on oneside of the street lots with fifty feet front and one hundred and fiftyfeet deep and that it is desired to lay out the plans of houses on saidlots, this can be rapidly done with my improved triangle by placing thehypotenuse of the latter against the positioning triangle 13 so that theright angle sides 2 and 3 of my triangle stand at right angles andparallel to the street, respectively, as seen in Fig. 3. In laying off alot one hundred and fifty feet deep, the scale 4 can be moved along theedge 2 of the triangle to bring a graduation point of the scale on theedge of the street and then the desired length for the depth of the lotcan be laid off directly from the scale. Assuming that the back line ofthe lot as measured from the scale 1 comes to the point 16, then thetriangle can be shifted on the positioning member 13 to bring the edge 3thereof in line with the point 16 thus laid 05, and by using the scaledthe width of the lot along its back line can be quickly marked 0E, andat the same time the back line of the lot can be drawn. In the same waylot after lot can be quickly laid off without the necessity of usingdividers for measuring ofl' distances and plans of houses can be plottedon the lots in the same way Without the necessity of using dividers.

Having fully described my invention, what I claim as new and desire tosecure by Letters Patent is 1. A right-angled triangle having a slidingscale member adjacent each of the two edges forming a right angle andmeans for sustaining each of said members for movement parallel to theedge of the triangle, said means permitting each member to be adjustedto and beyond the edge adjacent which the other member is situated.

2. The combination with a right angled triangle, of a reversible scalemember slidably mounted on each of the two edges fornr ing a rightangle, each scale member having its edge flush with the correspondingedge of the triangle in both of its positions, means for sustaining eachof said scale members for movement parallel to the edge of the triangle,said means permitting each member to be adjusted to and beyond the edgeflush with which the other member is situated,

3. A right-angled triangle having a track rigid therewith adjacent eachof the two edges forming a right angle, a scale slidably mounted on eachtrack, each track terminating short of the path of movement of the otherscale whereby each scale may slide by the end of the other in the sameplane therewith.

In testimony whereof, I have signed my name to this specification, inthe presence of two subscribing witnesses.

WALTER Gr. OLASSON.

Witnesses:

LESTER L. Foss, CHARLES A. J OSLIN.

Copies of this patent may be obtained for five cents each, by addressingthe Commissioner of Patents, Washington, D. G.

